Wireless communication devices are continuously integrating new and enhanced features and capabilities, that leverage an ability to remotely transmit and receive data using wireless communication capabilities. As the features and capabilities are added and/or enhanced, there often is a need to communicate wirelessly an ever increasing amount of information/data in order to support the added and/or enhanced features and capabilities of the device. However, increasing a device's ability to communicate information/data wirelessly is complicated by a further desire to limit the overall size of the device, which can sometimes make desirable an ability to share some of the circuitry and structure, which is used to support various forms of wireless communications.
Diplexers can facilitate the sharing of resources by allowing multiple separate signals to be merged onto a single terminal through frequency domain multiplexing. For example, a diplexer can help facilitate a pair of ports each respectively associated with its own transceiver being coupled to a common shared port that can be associated with a single antenna. Diplexer are generally different than a combiner or splitter in that each of the ports to be merged are often frequency selective, which can also serve to allow multiple separate signals to be merged while helping to reduce the potential for interference between the signals being merged.
Some forms of wireless cellular communications, in order to increase the rate of data that can be communicated, will allow a larger amount of frequency bandwidth to be utilized in support of the communication through carrier aggregation, which can sometimes make use of non-contiguous frequency bands. The increase in available bandwidth for supporting a particular communication will often allow for a corresponding increase in the bitrate of the data being communicated via a signal using the increased amount of allocated bandwidth.
Conventionally, bands having carrier frequencies below about 800 MHz are referred to as ultralow bands. Bands between 800 MHz and 1500 MHz are often referred to as low bands. Bands between 1500 MHz and 2200 MHz are often referred to as mid bands, and bands greater than 2200 MHz are often referred to as high bands. Previously, cellular service providers have supported a number of two-downlink carrier aggregation band combinations, including simultaneous ultralow band or low band operation with mid band or high band operation. At least some filter suppliers promote signal combining using various diplexers, triplexers and quadriplexers in the front end of the wireless radio frequency communication circuitry separate from the antenna matching circuitry. While diplexing, triplexing, etc. type circuits in the front end portion of the radio frequency communication circuitry can be cheaper than incorporating the diplexing, triplexing, etc. functionality in a tunable antenna match, this type of circuit can result in antenna matching in the context of a wideband signal, wherein carrier aggregation can involve a harmonic being produced by a tuner with respect to one of the bands being aggregated, which is in a band of interest in another one of the bands being aggregated. A tunable antenna match can sometimes involve the use of a variable capacitor, which in at least some instances can have a less than desired linear response, which in turn can increase the likelihood of an undesirable harmonic being produced. The presence of the tuner harmonic can sometimes result in the desensitizing of one or both of the receivers involved in the carrier aggregation operation.
The present innovators have correspondingly recognized that the harmful tuner harmonics associated with matching a wideband signal with an antenna through the use of a variable capacitor having a less than optimal linear response, which can have a harmful effect in at least some forms of carrier aggregation, can be addressed by introducing a trap across the tuner device in the matching circuitry for suppressing problematic tuner harmonic frequencies. By making the trap tunable, the trap can be adjusted to account for various different frequencies that may be problematic at different times, depending upon which ones of the carrier frequencies are currently being aggregated.